# HG changeset patch
# User Ryan C. Gordon <icculus@icculus.org>
# Date 1587708447 14400
#      Fri Apr 24 02:07:27 2020 -0400
# Node ID 7d6a82af06b3ad6f0d012418ccf179ced98dc5f2
# Parent  a564e72e3b2d0e422c8d8a80a7a5ad46487fb5d2
locale: First shot at SDL_GetPreferredLocales().

This was something I proposed a long time ago, Sylvain Becker did
additional work on it, then back to me. This is barely tested!

Fixes Bugzilla #2131.

diff --git a/Android.mk b/Android.mk
--- a/Android.mk
+++ b/Android.mk
@@ -35,6 +35,8 @@
 	$(wildcard $(LOCAL_PATH)/src/joystick/hidapi/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/joystick/virtual/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/loadso/dlopen/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/locale/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/locale/android/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/power/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/power/android/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/filesystem/android/*.c) \
diff --git a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -307,7 +307,7 @@
 
 set(SDL_SUBSYSTEMS
     Atomic Audio Video Render Events Joystick Haptic Power Threads Timers
-    File Loadso CPUinfo Filesystem Dlopen Sensor)
+    File Loadso CPUinfo Filesystem Dlopen Sensor Locale)
 foreach(_SUB ${SDL_SUBSYSTEMS})
   string(TOUPPER ${_SUB} _OPT)
   if (NOT DEFINED SDL_${_OPT}_ENABLED_BY_DEFAULT)
@@ -404,6 +404,7 @@
   ${SDL2_SOURCE_DIR}/src/events/*.c
   ${SDL2_SOURCE_DIR}/src/file/*.c
   ${SDL2_SOURCE_DIR}/src/libm/*.c
+  ${SDL2_SOURCE_DIR}/src/locale/*.c
   ${SDL2_SOURCE_DIR}/src/render/*.c
   ${SDL2_SOURCE_DIR}/src/render/*/*.c
   ${SDL2_SOURCE_DIR}/src/stdlib/*.c
@@ -885,6 +886,8 @@
   file(GLOB POWER_SOURCES ${SDL2_SOURCE_DIR}/src/power/*.c)
   set(SOURCE_FILES ${SOURCE_FILES} ${POWER_SOURCES})
 endif()
+
+
 # TODO: in configure.ac, the test for LOADSO and SDL_DLOPEN is a bit weird:
 # if LOADSO is not wanted, SDL_LOADSO_DISABLED is set
 # If however on Unix or APPLE dlopen() is detected via CheckDLOPEN(),
@@ -993,6 +996,11 @@
     set(SOURCE_FILES ${SOURCE_FILES} ${ANDROID_POWER_SOURCES})
     set(HAVE_SDL_POWER TRUE)
   endif()
+  if(SDL_LOCALE)
+    file(GLOB ANDROID_LOCALE_SOURCES ${SDL2_SOURCE_DIR}/src/locale/android/*.c)
+    set(SOURCE_FILES ${SOURCE_FILES} ${ANDROID_LOCALE_SOURCES})
+    set(HAVE_SDL_LOCALE TRUE)
+  endif()
   if(SDL_TIMERS)
     set(SDL_TIMER_UNIX 1)
     file(GLOB TIMER_SOURCES ${SDL2_SOURCE_DIR}/src/timer/unix/*.c)
@@ -1272,6 +1280,12 @@
     endif()
   endif()
 
+  if(SDL_LOCALE)
+    file(GLOB LOCALE_SOURCES ${SDL2_SOURCE_DIR}/src/locale/unix/*.c)
+    set(SOURCE_FILES ${SOURCE_FILES} ${LOCALE_SOURCES})
+    set(HAVE_SDL_LOCALE TRUE)
+  endif()
+
   if(SDL_FILESYSTEM)
     set(SDL_FILESYSTEM_UNIX 1)
     file(GLOB FILESYSTEM_SOURCES ${SDL2_SOURCE_DIR}/src/filesystem/unix/*.c)
@@ -1438,6 +1452,12 @@
     set(HAVE_SDL_POWER TRUE)
   endif()
 
+  if(SDL_LOCALE)
+    file(GLOB LOCALE_SOURCES ${SDL2_SOURCE_DIR}/src/locale/windows/*.c)
+    set(SOURCE_FILES ${SOURCE_FILES} ${LOCALE_SOURCES})
+    set(HAVE_SDL_LOCALE TRUE)
+  endif()
+
   if(SDL_FILESYSTEM)
     set(SDL_FILESYSTEM_WINDOWS 1)
     file(GLOB FILESYSTEM_SOURCES ${SDL2_SOURCE_DIR}/src/filesystem/windows/*.c)
@@ -1629,6 +1649,12 @@
     set(HAVE_SDL_POWER TRUE)
   endif()
 
+  if(SDL_LOCALE)
+    file(GLOB LOCALE_SOURCES ${SDL2_SOURCE_DIR}/src/locale/macosx/*.m)
+    set(SOURCE_FILES ${SOURCE_FILES} ${LOCALE_SOURCES})
+    set(HAVE_SDL_LOCALE TRUE)
+  endif()
+
   if(SDL_TIMERS)
     set(SDL_TIMER_UNIX 1)
     file(GLOB TIMER_SOURCES ${SDL2_SOURCE_DIR}/src/timer/unix/*.c)
@@ -1837,6 +1863,12 @@
     set(HAVE_SDL_TIMERS TRUE)
   endif()
 
+  if(SDL_LOCALE)
+    file(GLOB LOCALE_SOURCES ${SDL2_SOURCE_DIR}/src/locale/haiku/*.cc)
+    set(SOURCE_FILES ${SOURCE_FILES} ${LOCALE_SOURCES})
+    set(HAVE_SDL_LOCALE TRUE)
+  endif()
+
   CheckPTHREAD()
 
 elseif(RISCOS)
@@ -1899,6 +1931,11 @@
   file(GLOB FILESYSTEM_SOURCES ${SDL2_SOURCE_DIR}/src/filesystem/dummy/*.c)
   set(SOURCE_FILES ${SOURCE_FILES} ${FILESYSTEM_SOURCES})
 endif()
+if(NOT HAVE_SDL_LOCALE)
+  set(SDL_LOCALE_DISABLED 1)
+  file(GLOB LOCALE_SOURCES ${SDL2_SOURCE_DIR}/src/locale/dummy/*.c)
+  set(SOURCE_FILES ${SOURCE_FILES} ${LOCALE_SOURCES})
+endif()
 
 # We always need to have threads and timers around
 if(NOT HAVE_SDL_THREADS)
diff --git a/Makefile.in b/Makefile.in
--- a/Makefile.in
+++ b/Makefile.in
@@ -82,6 +82,7 @@
 	SDL_keyboard.h \
 	SDL_keycode.h \
 	SDL_loadso.h \
+	SDL_locale.h \
 	SDL_log.h \
 	SDL_main.h \
 	SDL_messagebox.h \
diff --git a/configure b/configure
--- a/configure
+++ b/configure
@@ -770,6 +770,7 @@
 docdir
 oldincludedir
 includedir
+runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -981,6 +982,7 @@
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
+runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE}'
@@ -1233,6 +1235,15 @@
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
+  -runstatedir | --runstatedir | --runstatedi | --runstated \
+  | --runstate | --runstat | --runsta | --runst | --runs \
+  | --run | --ru | --r)
+    ac_prev=runstatedir ;;
+  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
+  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
+  | --run=* | --ru=* | --r=*)
+    runstatedir=$ac_optarg ;;
+
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1370,7 +1381,7 @@
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir
+		libdir localedir mandir runstatedir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1523,6 +1534,7 @@
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
+  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -17309,6 +17321,7 @@
 SOURCES="$SOURCES $srcdir/src/timer/*.c"
 SOURCES="$SOURCES $srcdir/src/video/*.c"
 SOURCES="$SOURCES $srcdir/src/video/yuv2rgb/*.c"
+SOURCES="$SOURCES $srcdir/src/locale/*.c"
 
 
 # Check whether --enable-atomic was given.
@@ -24659,6 +24672,8 @@
 
 CheckEventSignals
 
+have_locale=no
+
 case "$host" in
     *-*-linux*|*-*-uclinux*|*-*-gnu*|*-*-k*bsd*-gnu|*-*-bsdi*|*-*-freebsd*|*-*-dragonfly*|*-*-netbsd*|*-*-openbsd*|*-*-sysv5*|*-*-solaris*|*-*-hpux*|*-*-aix*|*-*-minix*|*-*-nto*)
         case "$host" in
@@ -24746,6 +24761,9 @@
         CheckRPATH
         CheckVivanteVideo
 
+        SOURCES="$SOURCES $srcdir/src/locale/unix/*.c"
+        have_locale=yes
+
         # Set up files for the audio library
         if test x$enable_audio = xyes; then
           case $ARCH in
@@ -24923,6 +24941,10 @@
         # Set up the core platform files
         SOURCES="$SOURCES $srcdir/src/core/windows/*.c"
 
+        # Use the Windows locale APIs.
+        SOURCES="$SOURCES $srcdir/src/locale/windows/*.c"
+        have_locale=yes
+
         # Set up files for the video library
         if test x$enable_video = xyes; then
 
@@ -25174,6 +25196,11 @@
             SOURCES="$SOURCES $srcdir/src/filesystem/haiku/*.cc"
             have_filesystem=yes
         fi
+
+        # Set up files for the locale library
+        SOURCES="$SOURCES $srcdir/src/locale/haiku/*.cc"
+        have_locale=yes
+
         # The Haiku platform requires special setup.
         SOURCES="$srcdir/src/main/haiku/*.cc $SOURCES"
         EXTRA_LDFLAGS="$EXTRA_LDFLAGS -lroot -lbe -lmedia -lgame -ldevice -ltextencoding"
@@ -25216,6 +25243,10 @@
         CheckVulkan
         CheckPTHREAD
 
+        # Set up files for the locale library
+        SOURCES="$SOURCES $srcdir/src/locale/macosx/*.m"
+        have_locale=yes
+
         # Set up files for the audio library
         if test x$enable_audio = xyes; then
 
@@ -25337,6 +25368,10 @@
         CheckPTHREAD
         CheckHIDAPI
 
+        # Set up files for the locale library
+        SOURCES="$SOURCES $srcdir/src/locale/macosx/*.m"
+        have_locale=yes
+
         # Set up files for the audio library
         if test x$enable_audio = xyes; then
 
@@ -25549,6 +25584,9 @@
 
 # Verify that we have all the platform specific files we need
 
+if test x$have_locale != xyes; then
+    SOURCES="$SOURCES $srcdir/src/locale/dummy/*.c"
+fi
 if test x$have_joystick != xyes; then
     if test x$enable_joystick = xyes; then
 
diff --git a/configure.ac b/configure.ac
--- a/configure.ac
+++ b/configure.ac
@@ -413,6 +413,7 @@
 SOURCES="$SOURCES $srcdir/src/timer/*.c"
 SOURCES="$SOURCES $srcdir/src/video/*.c"
 SOURCES="$SOURCES $srcdir/src/video/yuv2rgb/*.c"
+SOURCES="$SOURCES $srcdir/src/locale/*.c"
 
 dnl Enable/disable various subsystems of the SDL library
 
@@ -3439,6 +3440,8 @@
 dnl Do this for every platform, but for some it doesn't mean anything, but better to catch it here anyhow.
 CheckEventSignals
 
+have_locale=no
+
 dnl Set up the configuration based on the host platform!
 case "$host" in
     *-*-linux*|*-*-uclinux*|*-*-gnu*|*-*-k*bsd*-gnu|*-*-bsdi*|*-*-freebsd*|*-*-dragonfly*|*-*-netbsd*|*-*-openbsd*|*-*-sysv5*|*-*-solaris*|*-*-hpux*|*-*-aix*|*-*-minix*|*-*-nto*)
@@ -3527,6 +3530,9 @@
         CheckRPATH
         CheckVivanteVideo
 
+        SOURCES="$SOURCES $srcdir/src/locale/unix/*.c"
+        have_locale=yes
+
         # Set up files for the audio library
         if test x$enable_audio = xyes; then
           case $ARCH in
@@ -3676,6 +3682,10 @@
         # Set up the core platform files
         SOURCES="$SOURCES $srcdir/src/core/windows/*.c"
 
+        # Use the Windows locale APIs.
+        SOURCES="$SOURCES $srcdir/src/locale/windows/*.c"
+        have_locale=yes
+
         # Set up files for the video library
         if test x$enable_video = xyes; then
             AC_DEFINE(SDL_VIDEO_DRIVER_WINDOWS, 1, [ ])
@@ -3847,6 +3857,11 @@
             SOURCES="$SOURCES $srcdir/src/filesystem/haiku/*.cc"
             have_filesystem=yes
         fi
+
+        # Set up files for the locale library
+        SOURCES="$SOURCES $srcdir/src/locale/haiku/*.cc"
+        have_locale=yes
+
         # The Haiku platform requires special setup.
         SOURCES="$srcdir/src/main/haiku/*.cc $SOURCES"
         EXTRA_LDFLAGS="$EXTRA_LDFLAGS -lroot -lbe -lmedia -lgame -ldevice -ltextencoding"
@@ -3867,6 +3882,10 @@
         CheckVulkan
         CheckPTHREAD
 
+        # Set up files for the locale library
+        SOURCES="$SOURCES $srcdir/src/locale/macosx/*.m"
+        have_locale=yes
+
         # Set up files for the audio library
         if test x$enable_audio = xyes; then
             AC_DEFINE(SDL_AUDIO_DRIVER_COREAUDIO, 1, [ ])
@@ -3966,6 +3985,10 @@
         CheckPTHREAD
         CheckHIDAPI
 
+        # Set up files for the locale library
+        SOURCES="$SOURCES $srcdir/src/locale/macosx/*.m"
+        have_locale=yes
+
         # Set up files for the audio library
         if test x$enable_audio = xyes; then
             AC_DEFINE(SDL_AUDIO_DRIVER_COREAUDIO, 1, [ ])
@@ -4141,6 +4164,9 @@
 
 # Verify that we have all the platform specific files we need
 
+if test x$have_locale != xyes; then
+    SOURCES="$SOURCES $srcdir/src/locale/dummy/*.c"
+fi
 if test x$have_joystick != xyes; then
     if test x$enable_joystick = xyes; then
         AC_DEFINE(SDL_JOYSTICK_DUMMY, 1, [ ])
diff --git a/include/SDL.h b/include/SDL.h
--- a/include/SDL.h
+++ b/include/SDL.h
@@ -59,6 +59,7 @@
 #include "SDL_timer.h"
 #include "SDL_version.h"
 #include "SDL_video.h"
+#include "SDL_locale.h"
 
 #include "begin_code.h"
 /* Set up for C function definitions, even when using C++ */
diff --git a/include/SDL_events.h b/include/SDL_events.h
--- a/include/SDL_events.h
+++ b/include/SDL_events.h
@@ -85,6 +85,8 @@
                                      Called on Android in onResume()
                                 */
 
+    SDL_LOCALECHANGED,  /**< The user's locale preferences have changed. */
+
     /* Display events */
     SDL_DISPLAYEVENT   = 0x150,  /**< Display state change */
 
diff --git a/include/SDL_hints.h b/include/SDL_hints.h
--- a/include/SDL_hints.h
+++ b/include/SDL_hints.h
@@ -1292,7 +1292,7 @@
  */
 #define SDL_HINT_WAVE_FACT_CHUNK   "SDL_WAVE_FACT_CHUNK"
 
-/*
+/**
  *  \brief Override for SDL_GetDisplayUsableBounds()
  *
  *  If set, this hint will override the expected results for
@@ -1307,6 +1307,21 @@
 #define SDL_HINT_DISPLAY_USABLE_BOUNDS "SDL_DISPLAY_USABLE_BOUNDS"
 
 /**
+ *  \brief Override for SDL_GetPreferredLocales()
+ *
+ *  If set, this will be favored over anything the OS might report for the
+ *  user's preferred locales. Changing this hint at runtime will not generate
+ *  a SDL_LOCALECHANGED event (but if you can change the hint, you can push
+ *  your own event, if you want).
+ *
+ *  The format of this hint is a comma-separated list of language and locale,
+ *  combined with an underscore, as is a common format: "en_GB". Locale is
+ *  optional: "en". So you might have a list like this: "en_GB,jp,es_PT"
+ */
+#define SDL_HINT_PREFERRED_LOCALES "SDL_PREFERRED_LOCALES"
+
+
+/**
  *  \brief  An enumeration of hint priorities
  */
 typedef enum
diff --git a/include/SDL_locale.h b/include/SDL_locale.h
new file mode 100644
--- /dev/null
+++ b/include/SDL_locale.h
@@ -0,0 +1,101 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+/**
+ *  \file SDL_locale.h
+ *
+ *  Include file for SDL locale services
+ */
+
+#ifndef _SDL_locale_h
+#define _SDL_locale_h
+
+#include "SDL_stdinc.h"
+#include "SDL_error.h"
+
+#include "begin_code.h"
+/* Set up for C function definitions, even when using C++ */
+#ifdef __cplusplus
+/* *INDENT-OFF* */
+extern "C" {
+/* *INDENT-ON* */
+#endif
+
+
+typedef struct SDL_Locale
+{
+    const char *language;  /**< A language name, like "en" for English. */
+    const char *country;  /**< A country, like "US" for America. Can be NULL. */
+} SDL_Locale;
+
+/**
+ *  \brief Report the user's preferred locale.
+ *
+ *  This returns an array of SDL_Locale structs, the final item zeroed out.
+ *  When the caller is done with this array, it should call SDL_free() on
+ *  the returned value; all the memory involved is allocated in a single
+ *  block, so a single SDL_free() will suffice.
+ *
+ *  Returned language strings are in the format xx, where 'xx' is an ISO-639
+ *  language specifier (such as "en" for English, "de" for German, etc).
+ *  Country strings are in the format YY, where "YY" is an ISO-3166 country
+ *  code (such as "US" for the United States, "CA" for Canada, etc). Country
+ *  might be NULL if there's no specific guidance on them (so you might get
+ *  { "en", "US" } for American English, but { "en", NULL } means "English
+ *  language, generically"). Language strings are never NULL, except to
+ *  terminate the array.
+ *
+ *  Please note that not all of these strings are 2 characters; some are
+ *  three or more.
+ *
+ *  The returned list of locales are in the order of the user's preference.
+ *  For example, a German citizen that is fluent in US English and knows
+ *  enough Japanese to navigate around Tokyo might have a list like:
+ *  { "de", "en_US", "jp", NULL }. Someone from England might prefer British
+ *  English (where "color" is spelled "colour", etc), but will settle for
+ *  anything like it: { "en_GB", "en", NULL }.
+ *
+ *  This function returns NULL on error, including when the platform does not
+ *  supply this information at all.
+ *
+ *  This might be a "slow" call that has to query the operating system. It's
+ *  best to ask for this once and save the results. However, this list can
+ *  change, usually because the user has changed a system preference outside
+ *  of your program; SDL will send an SDL_LOCALECHANGED event in this case,
+ *  if possible, and you can call this function again to get an updated copy
+ *  of preferred locales.
+ *
+ *   \return array of locales, terminated with a locale with a NULL language
+ *           field. Will return NULL on error.
+ */
+extern DECLSPEC SDL_Locale * SDLCALL SDL_GetPreferredLocales(void);
+
+/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+/* *INDENT-OFF* */
+}
+/* *INDENT-ON* */
+#endif
+#include "close_code.h"
+
+#endif /* _SDL_locale_h */
+
+/* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/core/android/SDL_android.c b/src/core/android/SDL_android.c
--- a/src/core/android/SDL_android.c
+++ b/src/core/android/SDL_android.c
@@ -44,6 +44,8 @@
 #include "../../haptic/android/SDL_syshaptic_c.h"
 
 #include <android/log.h>
+#include <android/configuration.h>
+#include <android/asset_manager_jni.h>
 #include <sys/system_properties.h>
 #include <pthread.h>
 #include <sys/types.h>
@@ -2796,6 +2798,82 @@
 	return bPermissionRequestResult;
 }
 
+int Android_JNI_GetLocale(char *buf, size_t buflen)
+{
+    struct LocalReferenceHolder refs = LocalReferenceHolder_Setup(__FUNCTION__);
+    JNIEnv* env = Android_JNI_GetEnv();
+    int retval = -1;
+
+    JNIEnv *mEnv = Android_JNI_GetEnv();
+    if (!LocalReferenceHolder_Init(&refs, env)) {
+        LocalReferenceHolder_Cleanup(&refs);
+        return -1;
+    }
+
+    SDL_assert(buflen > 6);
+
+    jmethodID mid;
+    jobject context;
+    jobject assetManager;
+
+    /* context = SDLActivity.getContext(); */
+    mid = (*mEnv)->GetStaticMethodID(mEnv, mActivityClass,
+            "getContext","()Landroid/content/Context;");
+    context = (*mEnv)->CallStaticObjectMethod(mEnv, mActivityClass, mid);
+
+    /* assetManager = context.getAssets(); */
+    mid = (*mEnv)->GetMethodID(mEnv, (*mEnv)->GetObjectClass(mEnv, context),
+            "getAssets", "()Landroid/content/res/AssetManager;");
+    assetManager = (*mEnv)->CallObjectMethod(mEnv, context, mid);
+
+
+    /* API from NDK: android/configuration.h */
+    /* API from NDK: android/asset_manager_jni.h */
+    AAssetManager* asset_mgr = AAssetManager_fromJava(env, assetManager);
+    AConfiguration *cfg = AConfiguration_new();
+
+    if (asset_mgr && cfg)
+    {
+        char language[2] = {};
+        char country[2] = {};
+        size_t id = 0;
+
+        AConfiguration_fromAssetManager(cfg, asset_mgr);
+        AConfiguration_getLanguage(cfg, language);
+        AConfiguration_getCountry(cfg, country);
+
+        retval = 0;
+
+        /* copy language (not null terminated) */
+        if (language[0]) {
+            buf[id++] = language[0];
+            if (language[1]) {
+                buf[id++] = language[1];
+            }
+        }
+
+        buf[id++] = '_';
+
+        /* copy country (not null terminated) */
+        if (country[0]) {
+            buf[id++] = country[0];
+            if (country[1]) {
+                buf[id++] = country[1];
+            }
+        }
+        
+        buf[id++] = '\0';
+        SDL_assert(id <= buflen);
+    }
+
+    if (cfg) {
+        AConfiguration_delete(cfg);
+    }
+
+    LocalReferenceHolder_Cleanup(&refs);
+    return retval;
+}
+
 #endif /* __ANDROID__ */
 
 /* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/core/android/SDL_android.h b/src/core/android/SDL_android.h
--- a/src/core/android/SDL_android.h
+++ b/src/core/android/SDL_android.h
@@ -104,6 +104,9 @@
 JNIEnv *Android_JNI_GetEnv(void);
 int Android_JNI_SetupThread(void);
 
+/* Locale */
+int Android_JNI_GetLocale(char *buf, size_t buflen);
+
 /* Generic messages */
 int Android_JNI_SendMessage(int command, int param);
 
diff --git a/src/dynapi/SDL_dynapi_overrides.h b/src/dynapi/SDL_dynapi_overrides.h
--- a/src/dynapi/SDL_dynapi_overrides.h
+++ b/src/dynapi/SDL_dynapi_overrides.h
@@ -763,3 +763,4 @@
 #define SDL_Metal_GetDrawableSize SDL_Metal_GetDrawableSize_REAL
 #define SDL_trunc SDL_trunc_REAL
 #define SDL_truncf SDL_truncf_REAL
+#define SDL_GetPreferredLocales SDL_GetPreferredLocales_REAL
diff --git a/src/dynapi/SDL_dynapi_procs.h b/src/dynapi/SDL_dynapi_procs.h
--- a/src/dynapi/SDL_dynapi_procs.h
+++ b/src/dynapi/SDL_dynapi_procs.h
@@ -822,3 +822,4 @@
 SDL_DYNAPI_PROC(void,SDL_Metal_GetDrawableSize,(SDL_Window *a, int *b, int *c),(a,b,c),)
 SDL_DYNAPI_PROC(double,SDL_trunc,(double a),(a),return)
 SDL_DYNAPI_PROC(float,SDL_truncf,(float a),(a),return)
+SDL_DYNAPI_PROC(SDL_Locale *,SDL_GetPreferredLocales,(void),(),return)
diff --git a/src/events/SDL_events.c b/src/events/SDL_events.c
--- a/src/events/SDL_events.c
+++ b/src/events/SDL_events.c
@@ -1010,6 +1010,12 @@
 }
 
 int
+SDL_SendLocaleChangedEvent(void)
+{
+    return SDL_SendAppEvent(SDL_LOCALECHANGED);
+}
+
+int
 SDL_EventsInit(void)
 {
     SDL_AddHintCallback(SDL_HINT_EVENT_LOGGING, SDL_EventLoggingChanged, NULL);
diff --git a/src/events/SDL_events_c.h b/src/events/SDL_events_c.h
--- a/src/events/SDL_events_c.h
+++ b/src/events/SDL_events_c.h
@@ -46,6 +46,7 @@
 extern int SDL_SendAppEvent(SDL_EventType eventType);
 extern int SDL_SendSysWMEvent(SDL_SysWMmsg * message);
 extern int SDL_SendKeymapChangedEvent(void);
+extern int SDL_SendLocaleChangedEvent(void);
 
 extern int SDL_SendQuit(void);
 
diff --git a/src/events/SDL_gesture.c b/src/events/SDL_gesture.c
--- a/src/events/SDL_gesture.c
+++ b/src/events/SDL_gesture.c
@@ -36,7 +36,7 @@
 
 #define MAXPATHSIZE 1024
 
-#define ENABLE_DOLLAR
+// PATCH slvn #define ENABLE_DOLLAR
 
 #define DOLLARNPOINTS 64
 
diff --git a/src/locale/SDL_locale.c b/src/locale/SDL_locale.c
new file mode 100644
--- /dev/null
+++ b/src/locale/SDL_locale.c
@@ -0,0 +1,103 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "../SDL_internal.h"
+#include "SDL_syslocale.h"
+#include "SDL_hints.h"
+
+static SDL_Locale *
+build_locales_from_csv_string(char *csv)
+{
+    size_t num_locales = 1;  /* at least one */
+    size_t slen;
+    size_t alloclen;
+    char *ptr;
+    SDL_Locale *loc;
+    SDL_Locale *retval;
+
+    if (!csv || !csv[0]) {
+        return NULL;  /* nothing to report */
+    }
+
+    for (ptr = csv; *ptr; ptr++) {
+        if (*ptr == ',') {
+            num_locales++;
+        }
+    }
+
+    num_locales++;  /* one more for terminator */
+
+    slen = ((size_t) (ptr - csv)) + 1;  /* strlen(csv) + 1 */
+    alloclen = slen + (num_locales * sizeof (SDL_Locale));
+
+    loc = retval = (SDL_Locale *) SDL_calloc(1, alloclen);
+    if (!retval) {
+        SDL_OutOfMemory();
+        return NULL;  /* oh well */
+    }
+    ptr = (char *) (retval + num_locales);
+    SDL_strlcpy(ptr, csv, slen);
+
+    while (SDL_TRUE) {  /* parse out the string */
+        while (*ptr == ' ') ptr++;  /* skip whitespace. */
+        if (*ptr == '\0') {
+            break;
+        }
+        loc->language = ptr++;
+        while (SDL_TRUE) {
+            const char ch = *ptr;
+            if (ch == '_') {
+                *(ptr++) = '\0';
+                loc->country = ptr;
+            } else if (ch == ' ') {
+                *(ptr++) = '\0';  /* trim ending whitespace and keep going. */
+            } else if (ch == ',') {
+                *(ptr++) = '\0';
+                loc++;
+                break;
+            } else if (ch == '\0') {
+                loc++;
+                break;
+            } else {
+                ptr++;  /* just keep going, still a valid string */
+            }
+        }
+    }
+
+    return retval;
+}
+
+SDL_Locale *
+SDL_GetPreferredLocales(void)
+{
+    char locbuf[128];  /* enough for 21 "xx_YY," language strings. */
+    const char *hint = SDL_GetHint(SDL_HINT_PREFERRED_LOCALES);
+    if (hint) {
+        SDL_strlcpy(locbuf, hint, sizeof (locbuf));
+    } else {
+        SDL_zeroa(locbuf);
+        SDL_SYS_GetPreferredLocales(locbuf, sizeof (locbuf));
+    }
+    return build_locales_from_csv_string(locbuf);
+}
+
+/* vi: set ts=4 sw=4 expandtab: */
+
diff --git a/src/locale/SDL_syslocale.h b/src/locale/SDL_syslocale.h
new file mode 100644
--- /dev/null
+++ b/src/locale/SDL_syslocale.h
@@ -0,0 +1,29 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "SDL_config.h"
+
+/* This is the system specific header for the SDL locale API */
+
+#include "SDL_locale.h"
+
+extern void SDL_SYS_GetPreferredLocales(char *buf, size_t buflen);
+
+/* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/locale/android/SDL_syslocale.c b/src/locale/android/SDL_syslocale.c
new file mode 100644
--- /dev/null
+++ b/src/locale/android/SDL_syslocale.c
@@ -0,0 +1,32 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_config.h"
+#include "../SDL_syslocale.h"
+
+void
+SDL_SYS_GetPreferredLocales(char *buf, size_t buflen)
+{
+    Android_JNI_GetLocale(buf, buflen);
+}
+
+/* vi: set ts=4 sw=4 expandtab: */
+
diff --git a/src/locale/dummy/SDL_syslocale.c b/src/locale/dummy/SDL_syslocale.c
new file mode 100644
--- /dev/null
+++ b/src/locale/dummy/SDL_syslocale.c
@@ -0,0 +1,33 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_config.h"
+#include "../SDL_syslocale.h"
+
+void
+SDL_SYS_GetPreferredLocales(char *buf, size_t buflen)
+{
+    /* dummy implementation. Caller already zero'd out buffer. */
+    SDL_Unsupported();
+}
+
+/* vi: set ts=4 sw=4 expandtab: */
+
diff --git a/src/locale/haiku/SDL_syslocale.cc b/src/locale/haiku/SDL_syslocale.cc
new file mode 100644
--- /dev/null
+++ b/src/locale/haiku/SDL_syslocale.cc
@@ -0,0 +1,72 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include <LocaleRoster.h>
+
+#include "SDL_config.h"
+#include "../SDL_syslocale.h"
+
+void
+SDL_SYS_GetPreferredLocales(char *buf, size_t buflen)
+{
+    BMessage msg;
+    if (BLocaleRoster::Default()->GetPreferredLanguages(&msg) != B_OK) {
+        SDL_SetError("BLocaleRoster couldn't get preferred languages");
+        return;
+    }
+
+    const char *key = "language";
+    type_code typ = B_ANY_TYPE;
+    int32 numlangs = 0;
+    if ((msg.GetInfo(key, &typ, &numlangs) != B_OK) || (typ != B_STRING_TYPE)) {
+        SDL_SetError("BLocaleRoster message was wrong");
+        return;
+    }
+
+    for (int32 i = 0; i < numlangs; i++) {
+        const char *str = NULL;
+        if (msg.FindString(key, i, &str) != B_OK) {
+            continue;
+        }
+
+        const size_t len = SDL_strlen(str);
+        if (buflen <= len) {
+            break;  // can't fit it, we're done.
+        }
+
+        SDL_strlcpy(buf, str, buflen);
+        buf += len;
+        buflen -= len;
+
+        if (i < (numlangs - 1)) {
+            if (buflen <= 1) {
+                break;  // out of room, stop looking.
+            }
+            buf[0] = ',';  // add a comma between entries.
+            buf[1] = '\0';
+            buf++;
+            buflen--;
+        }
+    }
+}
+
+/* vi: set ts=4 sw=4 expandtab: */
+
diff --git a/src/locale/macosx/SDL_syslocale.m b/src/locale/macosx/SDL_syslocale.m
new file mode 100644
--- /dev/null
+++ b/src/locale/macosx/SDL_syslocale.m
@@ -0,0 +1,76 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_config.h"
+#include "../SDL_syslocale.h"
+
+#import <Cocoa/Cocoa.h>
+
+void
+SDL_SYS_GetPreferredLocales(char *buf, size_t buflen)
+{ @autoreleasepool {
+    NSArray *languages = NSLocale.preferredLanguages;
+    size_t numlangs = 0;
+    size_t i;
+
+    numlangs = (size_t) [languages count];
+
+    for (i = 0; i < numlangs; i++) {
+        NSString *nsstr = [languages objectAtIndex:i];
+        size_t len;
+        char *ptr;
+
+        if (nsstr == nil) {
+            break;
+        }
+
+        [nsstr getCString:buf maxLength:buflen encoding:NSASCIIStringEncoding];
+        len = SDL_strlen(buf);
+
+        // convert '-' to '_'...
+        //  These are always full lang-COUNTRY, so we search from the back,
+        //  so things like zh-Hant-CN find the right '-' to convert.
+        if ((ptr = SDL_strrchr(buf, '-')) != NULL) {
+            *ptr = '_';
+        }
+
+        if (buflen <= len) {
+            *buf = '\0';  // drop this one and stop, we can't fit anymore.
+            break;
+        }
+
+        buf += len;
+        buflen -= len;
+
+        if (i < (numlangs - 1)) {
+            if (buflen <= 1) {
+                break;  // out of room, stop looking.
+            }
+            buf[0] = ',';  // add a comma between entries.
+            buf[1] = '\0';
+            buf++;
+            buflen--;
+        }
+    }
+}}
+
+/* vi: set ts=4 sw=4 expandtab: */
+
diff --git a/src/locale/unix/SDL_syslocale.c b/src/locale/unix/SDL_syslocale.c
new file mode 100644
--- /dev/null
+++ b/src/locale/unix/SDL_syslocale.c
@@ -0,0 +1,51 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_config.h"
+#include "../SDL_syslocale.h"
+
+void
+SDL_SYS_GetPreferredLocales(char *buf, size_t buflen)
+{
+    /* !!! FIXME: should we be using setlocale()? Or some D-Bus thing? */
+    /* !!! FIXME:  fallback locales are in LANGUAGE, check there. */
+    const char *envr = SDL_getenv("LANG");
+    if (envr == NULL) {
+        SDL_SetError("LANG environment variable isn't set");
+    } else {
+        char *ptr;
+
+        SDL_strlcpy(buf, envr, buflen);
+
+        ptr = SDL_strchr(buf, '.');  /* chop off encoding if specified. */
+        if (ptr != NULL) {
+            *ptr = '\0';
+        }
+
+        ptr = SDL_strchr(buf, '@');  /* chop off extra bits if specified. */
+        if (ptr != NULL) {
+            *ptr = '\0';
+        }
+    }
+}
+
+/* vi: set ts=4 sw=4 expandtab: */
+
diff --git a/src/locale/windows/SDL_syslocale.c b/src/locale/windows/SDL_syslocale.c
new file mode 100644
--- /dev/null
+++ b/src/locale/windows/SDL_syslocale.c
@@ -0,0 +1,54 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_config.h"
+#include "../SDL_syslocale.h"
+
+void
+SDL_SYS_GetPreferredLocales(char *buf, size_t buflen)
+{
+    /* !!! FIXME: there's a newer API in Windows Vista and later, try that first. */
+    const char **retval = NULL;
+    char lang[16];
+    char country[16];
+
+	const int langrc = GetLocaleInfoA(LOCALE_USER_DEFAULT,
+                                      LOCALE_SISO639LANGNAME,
+                                      lang, sizeof (lang));
+
+	const int ctryrc =  GetLocaleInfoA(LOCALE_USER_DEFAULT,
+                                       LOCALE_SISO3166CTRYNAME,
+                                       country, sizeof (country));
+
+    /* Win95 systems will fail, because they don't have LOCALE_SISO*NAME ... */
+    if (langrc == 0) {
+        SDL_SetError("Couldn't obtain language info");
+    } else {
+        if (ctryrc != 0) {
+            SDL_snprintf(buf, buflen, "%s_%s", lang, country);
+        } else {
+            SDL_strlcpy(buf, buflen, lang);
+        }
+    }
+}
+
+/* vi: set ts=4 sw=4 expandtab: */
+
diff --git a/src/locale/winrt/SDL_syslocale.c b/src/locale/winrt/SDL_syslocale.c
new file mode 100644
--- /dev/null
+++ b/src/locale/winrt/SDL_syslocale.c
@@ -0,0 +1,56 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "SDL_config.h"
+#include "../SDL_syslocale.h"
+
+using namespace Windows::Graphics::Display;
+#include <wchar.h>
+
+const char **
+SDL_SYS_GetLocales(void)
+{
+    WCHAR wbuffer[128] = "";
+    int ret = 0;
+
+    /* !!! FIXME: do we not have GetUserPreferredUILanguages on WinPhone or UWP? */
+# if WINAPI_FAMILY == WINAPI_FAMILY_PHONE_APP
+    ret = GetLocaleInfoEx(LOCALE_NAME_SYSTEM_DEFAULT, LOCALE_SNAME, wbuffer, SDL_arraylen(wbuffer));
+# else
+    ret = GetSystemDefaultLocaleName(wbuffer, SDL_arraylen(wbuffer));
+# endif
+
+    if (ret > 0)
+    {
+        /* Need to convert LPWSTR to LPSTR, that is wide char to char. */
+        int i;
+
+        if (ret >= (buflen - 1) ) {
+            ret = buflen - 1;
+        }
+        for (i = 0; i < ret; i++) {
+            buf[i] = (char) wbuffer[i];  /* assume this was ASCII anyhow. */
+        }
+    }
+}
+
+/* vi: set ts=4 sw=4 expandtab: */
+
diff --git a/src/video/cocoa/SDL_cocoaevents.m b/src/video/cocoa/SDL_cocoaevents.m
--- a/src/video/cocoa/SDL_cocoaevents.m
+++ b/src/video/cocoa/SDL_cocoaevents.m
@@ -117,6 +117,7 @@
 }
 
 - (id)init;
+- (void)localeDidChange:(NSNotification *)notification;
 @end
 
 @implementation SDLAppDelegate : NSObject
@@ -137,6 +138,11 @@
                    selector:@selector(focusSomeWindow:)
                        name:NSApplicationDidBecomeActiveNotification
                      object:nil];
+
+        [center addObserver:self
+                   selector:@selector(localeDidChange:)
+                       name:NSCurrentLocaleDidChangeNotification
+                     object:nil];
     }
 
     return self;
@@ -148,6 +154,7 @@
 
     [center removeObserver:self name:NSWindowWillCloseNotification object:nil];
     [center removeObserver:self name:NSApplicationDidBecomeActiveNotification object:nil];
+    [center removeObserver:self name:NSCurrentLocaleDidChangeNotification object:nil];
 
     [super dealloc];
 }
@@ -226,6 +233,11 @@
     }
 }
 
+- (void)localeDidChange:(NSNotification *)notification;
+{
+    SDL_SendLocaleChangedEvent();
+}
+
 - (BOOL)application:(NSApplication *)theApplication openFile:(NSString *)filename
 {
     return (BOOL)SDL_SendDropFile(NULL, [filename UTF8String]) && SDL_SendDropComplete(NULL);
diff --git a/test/Makefile.in b/test/Makefile.in
--- a/test/Makefile.in
+++ b/test/Makefile.in
@@ -37,6 +37,7 @@
 	testjoystick$(EXE) \
 	testkeys$(EXE) \
 	testloadso$(EXE) \
+	testlocale$(EXE) \
 	testlock$(EXE) \
 	testmessage$(EXE) \
 	testmultiaudio$(EXE) \
@@ -303,6 +304,10 @@
 testvulkan$(EXE): $(srcdir)/testvulkan.c
 	$(CC) -o $@ $^ $(CFLAGS) $(LIBS)
 
+testlocale$(EXE): $(srcdir)/testlocale.c
+	$(CC) -o $@ $? $(CFLAGS) $(LIBS)
+
+
 
 clean:
 	rm -f $(TARGETS)
diff --git a/test/README b/test/README
--- a/test/README
+++ b/test/README
@@ -12,6 +12,7 @@
 	testjoystick	List joysticks and watch joystick events
 	testkeys	List the available keyboard keys
 	testloadso	Tests the loadable library layer
+	testlocale  Test Locale API
 	testlock	Hacked up test of multi-threading and locking
 	testmultiaudio	Tests using several audio devices
 	testoverlay2	Tests the overlay flickering/scaling during playback.
diff --git a/test/configure b/test/configure
--- a/test/configure
+++ b/test/configure
@@ -640,6 +640,7 @@
 docdir
 oldincludedir
 includedir
+runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -720,6 +721,7 @@
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
+runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE}'
@@ -972,6 +974,15 @@
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
+  -runstatedir | --runstatedir | --runstatedi | --runstated \
+  | --runstate | --runstat | --runsta | --runst | --runs \
+  | --run | --ru | --r)
+    ac_prev=runstatedir ;;
+  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
+  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
+  | --run=* | --ru=* | --r=*)
+    runstatedir=$ac_optarg ;;
+
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1109,7 +1120,7 @@
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir
+		libdir localedir mandir runstatedir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1262,6 +1273,7 @@
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
+  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
diff --git a/test/testlocale.c b/test/testlocale.c
new file mode 100644
--- /dev/null
+++ b/test/testlocale.c
@@ -0,0 +1,65 @@
+/*
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely.
+*/
+#include <stdio.h>
+#include "SDL.h"
+
+/* !!! FIXME: move this to the test framework */
+
+static void log_locales(void)
+{
+    SDL_Locale *locales = SDL_GetPreferredLocales();
+    if (locales == NULL) {
+        SDL_Log("Couldn't determine locales.");
+    } else {
+        SDL_Locale *l;
+        SDL_Log("Locales, in order of preference:");
+        for (l = locales; l->language; l++) {
+            const char *c = l->country;
+            SDL_Log(" - %s%s%s", l->language, c ? "_" : "", c ? c : "");
+        }
+        SDL_Log("");
+        SDL_free(locales);
+    }
+}
+
+int main(int argc, char **argv)
+{
+    /* Enable standard application logging */
+    SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
+
+    /* Print locales and languages */
+    if (SDL_Init(SDL_INIT_VIDEO) != -1) {
+        log_locales();
+
+        if ((argc == 2) && (SDL_strcmp(argv[1], "--listen") == 0)) {
+            SDL_bool keep_going = SDL_TRUE;
+            while (keep_going) {
+                SDL_Event e;
+                while (SDL_PollEvent(&e)) {
+                    if (e.type == SDL_QUIT) {
+                        keep_going = SDL_FALSE;
+                    } else if (e.type == SDL_LOCALECHANGED) {
+                        SDL_Log("Saw SDL_LOCALECHANGED event!");
+                        log_locales();
+                    }
+                }
+                SDL_Delay(10);
+            }
+        }
+
+        SDL_Quit();
+    }
+
+   return 0;
+}
+
+/* vi: set ts=4 sw=4 expandtab: */